Evaluating Stage Motion for Automated Electron Microscopy

TL;DR

This paper presents a framework for evaluating and improving stage motion in electron microscopes, addressing challenges like mechanical instability and thermal drift to enable more autonomous operation.

Contribution

It introduces a general evaluation framework, defines key metrics, and discusses fundamental hardware limits for automated stage control in electron microscopes.

Findings

Metrics for stage performance assessment

Proposed solutions for motion stability

Analysis of hardware limitations

Abstract

Precise control is an essential and elusive quality of emerging self-driving microscopes. It is widely understood these instruments must be capable of performing rapid, high-volume, and arbitrary movements for practical self-driving operation. However, stage movements are difficult to automate at scale, owing to mechanical instability, hysteresis, and thermal drift. Such difficulties pose major barriers to intelligent microscope designs that require repeatable, precise movements. To guide design of emerging instruments, it is necessary to understand the behavior of existing designs to identify rate limiting steps for full autonomy. Here we describe a general framework to evaluate stage motion in any electron microscope. We define metrics to evaluate stage degrees of freedom, propose solutions to improve performance, and comment on fundamental limits to automated experimentation using present hardware.